Re: Too much postmaster prozesses / CPU near 100% - Mailing list pgsql-novice

Thanks Josh,

but I dont think, that the connection-type is
the Problem.
I dont have found any helpful articles in the
Mailing-List Archive. I am Member in the php-list too :-)
We have rewritten our open-function for postgres.
We have the same Effect, all the same whether we
connect persistant or non-persistant.

Maybe i dont have exactly described our Problem:

With our "old" Server (MMX-233, 256MB RAM, Linux 2.2.16, Postgres 7.0.3)
we dont had any Probs.
After we run the new Server, some hours all things are ok.
And then, suddenly the machine creates many postmaster-processes in
a few seconds. Other System-Functions works now likewise not correct
(top: CPU-Idle 62985,2 %; /etc/init.d/postmaster stop = failed;
but /etc/init.d/postmaster start = postmaster already running;
"/proc not mounted"; "too many open files in system"; <-- examples)
We must "crash" the postmaster (kill -15 or kill-9) and restart apache
and start postmaster again.
And then, all things works correct again for some time (minutes or hours).
(Info: we run vacuumdb 1-2 times a day).

I think, the problem is handling of shared memory either in Postgres 7.1.3
or in Kernel 2.4.x or both.

Don't know how to fix the Prob. Consultants from Hewlett-Packard AND
RedHat don't know too. Info: Our new Server HP-LC2000r is certified
with RedHat7.1 and does NOT run with kernel 2.2.x :-((

Greez,
Michael

-----Ursprüngliche Nachricht-----
Von: Josh Berkus [mailto:josh@agliodbs.com]
Gesendet: Freitag, 26. Oktober 2001 22:06
An: Roth, Michael J.; 'pgsql-novice@postgresql.org'
Betreff: Re: [NOVICE] Too much postmaster prozesses / CPU near 100%

Michael,

> first excuse my bad english (my german is better :) ).

It's okay -- my German is terrible, so we're even.

> If 2 users connects the postmaster forks 30 (!!)
> processes, and they do never die.
> If 50 Users connects, over 300 postmaster-processes running
> and the CPU-States are nearly 100%, so we must stop and
> start the postmaster or reboot the server.

There are issues with PHP persistent connections and PostgreSQL which
cause exactly the problem you're having.  They are fixable, but involve
some tradeoffs.

Go to the PGSQL-PHP list archives and comb through them; much of the
discussion for the past year has been about persistent. pooled, and
other connection strategies.  See:
http://archives2.us.postgresql.org/pgsql-php/

You also may wish to join the PGSQL-PHP list, as well as the PGSQL-SQL
list.

-Josh

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